The present invention relates to an ultrasound diagnostic apparatus which diagnoses the inside of a subject, such as a human body, using an ultrasound probe having a plurality of ultrasound transducers, a method of transmitting and receiving an ultrasonic wave which transmits and receives an ultrasonic wave from an ultrasound probe to a subject, a program for transmitting and receiving an ultrasonic wave which causes a computer to execute a plurality of steps of the method of transmitting and receiving an ultrasonic wave, that is, a plurality of steps of transmitting and receiving an ultrasonic wave, and a computer readable recording medium having recorded therein the program for transmitting and receiving an ultrasonic wave. In particular, the present invention relates to a technique for allowing paracentesis or the like in which a puncture needle is inserted into a subject while viewing an ultrasound image.
An ultrasound vibrator which is used in an ultrasound diagnostic apparatus is formed by integrating a plurality of ultrasound transducers (vibrators). A transmit aperture and a receive aperture are set on each of a plurality of ultrasound transducers at the time of transmission and reception of an ultrasonic wave, and the delay time (delay amount) of each of the transmission output of the transmit aperture and the reception output of the receive aperture of each ultrasound transducer is appropriately controlled for each ultrasound transducer. An ultrasonic transmission beam and an ultrasonic reception beam are respectively synthesized to obtain ultrasound reception image data.
An ultrasound diagnostic apparatus is known which has a structure (puncture adapter) in which a puncture needle can be attached to an ultrasound probe such that a biopsy on a specific site in a subject as a measurement target can be easily performed using a dedicated puncture needle. In this apparatus, a guideline when the puncture needle is inserted is displayed on a display. If the ultrasound diagnostic apparatus is operated using the ultrasound probe while the puncture needle is inserted into the subject in accordance with the guideline, an operator can simultaneously confirm an image in the subject and the motion of the puncture needle on the display, thereby performing safe paracentesis (biopsy, drainage, or the like).
However, in the ultrasound diagnostic apparatus of the related art, there is a problem that the intensity of an echo signal from the puncture needle is weak depending on the entrance angle of the puncture needle, and the image of the puncture needle is difficult to view on the display. As a method of solving this problem, a technique is known in which the surface of the tip of the puncture needle is processed roughly (roughened). However, this technique has a problem in that an echo signal from other than the tip of the puncture needle is not sufficiently intensified, and it is not sufficient to intensify the echo signal itself.
For this reason, JP 9-28708 A describes a technique which, when a puncture needle is inserted into a subject, adjusts the transmission beam direction of an ultrasound scan beam at substantially a right angle with respect to the entrance path of the puncture needle, and controls the delay amount of the output of each ultrasound transducer such that the transmission beam focal point position of each scan beam is in the vicinity of the position of the puncture needle.